Defending Coast to Coast champion Braden Currie has dismissed the notion of using elder brother, Glen, as an ally to wear down five-time winner and rival Richard Ussher in tomorrow's Longest Day race.

The Curries are expected to be at the front of the pack of the 243km multisport endurance race across the South Island. Braden, 27, claimed his first title last year in a time of 11hr 06min 51sec, while Glen, 31, is back competing in the event again after a third place effort in 2011.

Ussher will be determined to reclaim the Longest Day crown after finishing second last year, almost six minutes behind Currie.

Braden said plenty of people had enquired whether he would team up strategically with his brother to set the pace and help support each other.

He ruled out the possibility and admitted they were more focused on their own individual efforts.

"What do you do? If we could, we'd try, but we're not going to sabotage our own race," Braden said.

"I'm not going to give up my race to let Glen have more of a chance and he's not going to give up his race to give me more of a chance.

"There's definitely not anything planned where we're going to go and take Richard out."

He had an enormous amount of respect for Ussher, competing with him in four events last year, while also training together. Currie expected he would be as difficult to beat as ever.

"When it comes to racing, I know he's as clever as always. He'll definitely race hard. I won't expect him to ease up this year and take second."

Currie was a surprise winner of last year's Longest Day, breaking away from Ussher on the 34km mountain run over Goat Pass to Klondyke Corner and managed to hang onto his lead. Currie, who hails from Methven, became the youngest person to win the Longest Day at just 26.

The victory had been a life-changing experience. He gained a sponsorship deal with Red Bull, which had enabled him to concentrate on being a fulltime athlete. Twelve months earlier, Currie had contemplated chucking in multisport, because of the challenge of running a busy cycle touring company in Australia.

He has enjoyed a phenomenal past year, finishing fifth at the Xterra world championship, winning the Challenge Wanaka half, the Motatapu Xterra, Peak to Peak, and Mark Webber team challenge, to go along with a third placing at the Tauranga half ironman last month. Winning the Coast to Coast had helped open doors, he said.

"It was pretty incredible last year. It's such an iconic race to win. Things have really developed over the last year because of it. It's allowed me to carry on and do what I love doing. It's been an amazing year for us."

This year's Coast to Coast will be a family affair for the Curries, with elder sister, Anna, competing for the first time in the two-day race. Braden's wife, Sally, who is a naturopath, will organise his nutritional requirements.

Currie said he and Glen were extremely competitive growing up and confessed it would be a weird feeling to battle it out in the Coast to Coast for the first time together.

"It will be pretty interesting. Normally you feel pretty comfortable in your own little world, but when you've got someone who knows you so well ... I expect him to be right in the mix."

Race director Robin Judkins said it was the first time in more than 30 years a set of brothers were vying for the feature One Day race. He believed it would add another exciting dynamic to the race.

Currie acknowledged he would be unable to fly under the radar this year, with the leading contenders being fully aware of his strengths and weaknesses.

He said the benefit of being a fulltime athlete meant he was far more prepared than this time last year.

"I think I've got more to offer in that second part of the day than I ever have before ...

"I was pretty scared last year. I'm looking forward to getting in that boat [for the 67km kayak] and putting my head down and going 'I've done it before. Let's not look back and let's make this count'.

"Last year, I couldn't really believe [I was leading]."

Meanwhile, a new champion will be crowned in the women's Longest Day with two-time winner Sophie Hart not featuring.

Nelson's Elina Ussher, a winner in 2010 and 2012 will start as the favourite, with Wanaka-based Jess Simson, who shattered the record for the women's two-day race last year in 12hr 48min 11sec, another strong threat.

Both Ussher and Simson are run specialists, which means the race is likely to be decided by who has the best weakest discipline.

Auckland's Louise Mark, who was second in 2010 and fourth in 2011, should also be in contention.